Anthraquinone dye developers



United States Patent G 3,047,386 ANTHRAQUINONE DYE DEVELOPERS Elkan R.Blout, Belmont, and Myron S. Simon, Newton Center, Mass, assignors toPolaroid Corporation, Cambridge, Mass., a corporation of Delaware NDrawing. Filed Aug. 26, 1957, Ser. No. 680,437 22 Claims. (Cl. 96-29)This invention relates to photography and more particularly to products,compositions and processes for the development of photosensitive silverhalide elements.

It is one object of the present invention to provide novel processes andcompositions for the development of silver halide emulsions, in whichcolored developing agents are used to develop a latent image.

Another object is to provide novel processes and compositions for thedevelopment of silver halide emulsions, in which the novel developingagent is capable of devloping a latent image and imparting a reversed orpositive colored image of said latent image to a superposedimagereceiving material.

Still another object is to provide novel products, processes andcompositions suitable for use in preparing monochromatic andmultichromatic photographic images.

A further object is to provide novel compounds which are useful asintermediates and color-providing materials.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The invention accordingly comprises the processes involving the severalsteps and the relation and order of one or more of such steps withrespect to each of the others, and the products and compositionspossessing the features, properties and the relation of elements whichare exemplified in the following detailed disclosure, and the scope ofthe application of which will be indicated in the claims.

The novel photographic developing agents employed in this inventionpossess the properties of both dye and a developing agent; thus they maybe referred to as dye developers. The nature of these dye developerswill be described hereinafter.

The photographic processes and compositions disclosed herein areparticularly useful in the treatment of a latent image present in aphotosensitive element, such as an exposed silver halide emulsion,whereby a positive dye image thereof may be imparted to another element,herein referred to as an image-carrying or image-receiving element.

The copending application of Howard G. Rogers, Serial No. 415,073, filedMarch 9, 1954, now abandoned and replaced by a continuation-in-partthereof, Serial No. 748,421, filed July 14, 1958, which issued May 9,1961 as US. Patent No. 2,983,606, discloses diffusion transfer-reversalprocesses wherein a photographic negative material such as aphotographic element comprising an exposed silver halide emulsion layercontaining a latent image, is processed, using a dye developer, toimpart to an image-receiving element a reversed or positive dye image ofsaid latent image by permeating into said emulsion layer a suitableliquid processing composition and bringing said emulsion layer intosuperposed relationship with an appropriate image-receiving layer. It isan object of this invention to provide additional dye developerssuitable for use in such processes.

In carrying out the process of this invention, a photosensitive elementcontaining a silver halide emulsion is exposed and wetted with a liquidprocessing composition, for example, by immersing, coating, spraying,flowing, etc., in the dark, and the photosensitive element superposed,prior to, during or after wetting, on a sheetlike support element, whichmay be utilized as an imagereceiving element. In a preferred embodiment,the photosensitive element contains a layer of dye developer, and theliquid processing composition is applied to the photosensitive elementin a uniform layer as the photosensitive element is brought intosuperposed position with an image-receiving element. It is also withinthe scope of this invention to apply the liquid processing compositionprior to exposure, in accordance with the disclosure in the copendingapplication of Edwin H. Land, Serial No. 498,672, filed April 1, 1955.The liquid processing composition permeates the emulsion to provide asolution of dye developer substantially uniformly distributed therein.As the latent image is developed, the oxidation product of the dyedeveloper is immobilized or precipitated in situ with the developedsilver, thereby providing an imagewise distribution of unoxidized dyedeveloper dissolved in the liquid processing composition. Thisimmobilization is apparently, at least in part, due to a change in thesolubility characteristics of the dye developer upon oxidation,

and especially as regards its solubility in alkaline solution. It mayalso be due, in part, to a tanning effect on the emulsion by theoxidized developing agent. At least part of this imagewise distributionof unoxidized dye developer is transferred, by imbibition, to asuperposed image-receiving layer or element, said transfer substantiallyexcluding silver or oxidized dye developer. Under certain circumstances,the layer of the liquid processing composition may be utilized as theimage-receiving layer. The latter element receives a depthwisediffusion, from the emulsion, of unoxidized dye developer withoutappreciably disturbing the imagewise distribution thereof to provide areversed or positive, colored image of the developed image. Theimage-receiving element may contain agents adapted to mordant orotherwise fix the diffused, unoxidized dye developer. If the color ofthe difiused dye developer is affected by changes in the pH of theimagereceiving element, this pH may be adjusted in accordance withwell-known techniques to provide a pH aifording the desired color.Imbibition periods of approximately one minute have been found to givegood results, but this contact period may be adjusted where necessary tocompensate for variations in temperature or other conditions. Thedesired positive image is revealed by stripping the image-receivingelement from the photosensitive element at the end of the imbibitionperiod.

The dye developers of this invention may be utilized in thephotosensitive element, for example in, on or behind the silver halideemulsion, or they may be utilized in the image-receiving element or inthe liquid processing composition. In a preferred embodiment, a coatingor layer of the dye developer is placed behind the silver halideemulsion, i.e., on the side of the emulsion adapted to be located mostdistant from the photographed subject when the emulsion is exposed andpreferably also adapted to be most distant from the image-receivingelement when in superposed relationship therewith. Placing the dyedeveloper behind the emulsion layer, as in the preferred embodiment, hasthe advantage of providing increased contrast in the positive image, andalso minimizes any light-filtering action by the colored dye developer.In this preferred embodiment, the layer of dye developer may be appliedby using a coating solution containing about 0.5 to 8%, by weight, ofthe dye developer. Similar concentrations may be used if the dyedeveloper is utilized as a component of the liquid processingcomposition, concentrations as low as 0.2% in the liquid processingcomposition being suitable in certain instances.

The liquid processing composition above referred to comprises at leastan aqueous solution of an alkaline compound, for example, diethylamine,sodium hydroxide or sodium carbonate, and may contain the dye developer.

In some instances, it may contain a minor amount of a conventionaldeveloping agent. If the liquid processing composition is to be appliedto the emulsion by being spread thereon, preferably in a relativelythin, uniform layer, it may also include a viscosity-increasing compoundconstituting the film-forming material of the type which, when saidcomposition is spread and dried, will form a relatively firm andrelatively stable film. A preferred film-forming material is .a highmolecular weight polymer such as a polymeric, water-soluble ether inertto an alkali solution, as for example, a hydroxyethyl cellulose orsodium carboxymethyl cellulose. Other film-forming materials orthickening agents whose ability to increase viscosity is substantiallyunaffected when left in solution for a long period of time may also beused.

The novel dye developers of this invention may be represented by theformula:

wherein each X is a hydrogen, alkyl, alkoxy, halogen, or nitro group orR2 (EH-E Y CH OH2 Y RI radical, provided that at least one X and notmore than two Xs are said radicals; each Y is an unsubstituted,alkyl-substituted, or halogen-substituted ortho or para dihydroxyphenylgroup; R is a hydrogen, methyl or ethyl group; R is a hydrogen or alkylgroup and preferably an .alkyl group containing no more than carbonatoms such as methyl, ethyl, propyl, etc. groups; R is an alkylene groupand preferably an alkylene group containing no more than 5 carbon atomssuch as methylene CH ethylene CH CH propylene CH CH CH isopropylene CHOH CH3 1,4-butylene -CH CH CH CH 1,12-butylene -CH1OH 5H2 (EH, etc.groups; and each Z may be hydrogen, a sulfo, carboxyl, cyano, halogen,alkyl, aryl, aryloxy, alkoxy, sulfonamido or carboxamido group.

In a preferred embodiment, X in the one position is a R? J'H-R Y \CHOH2Yradical and each Y is a p-dihydroxyphenyl group. Such compounds may bepresented by the formula:

4 The preferred dye developer of this invention is I ll N02 01-[a-methyl-fi,6-bis(2,5-dihydroxyphenyl)-diethy1amino]-5-nitr0anthraquinone The novel compounds of this invention may beprepared by condensing a suitable halogen or nitro-substitutedanthraquinone with an amine of the structure or a salt thereof, whereinY, R R and R have the same meaning as above. As examples of suitablehalogen and nitro-substituted anthraq'uinones useful in preparing thedye developers of this invention, mention may be made ofl-nitroanthraquinone, 1,5-dinitroanthraquinone, 1,8-dinitroanthraquinone, l-chloroanthraquinone and1,4-dichloroanthraquinone.

Amines within Formula A may be prepared by the processes disclosed inthe copending application of Elkan R. Blout, Milton Green and Myron S.Simon, Serial No. 680,405, filed August 26, 1957, now U.S. Patent No.2,949,359 issued August 16, 1960.

As an example of such an amine, mention may be made of:

It should be noted that it is within the scope of this invention to usea mixture of the novel dye developers of this invention in the processesherein disclosed. Thus, in certain instances it is unnecessary toseparate a mixture of mono and disubstituted material which may beproduced as a result of the synthesis, or to remove residualalkali-insoluble starting materials.

The following non-limiting example illustrates the preparation of anovel dye developer of this invention.

Example I 0.75 gm. of 1,5-dinitroanthraquinone, 4.8 gins. of amethyl 5,5bis-(2,5-dihydroxyphenyl)-diethylamine hydrobromide and 1.06 gms. ofsodium acetate are dissolved in 8 cc. of pyridine and 1 cc. of water.The solution is deaerated with nitrogen and refluxed for five hours. Thesolution becomes magenta almost immediately and then turns red afterabout a half hour. At the end of the reflux period, the product isprecipitated with dilute hydrochloric acid, filtered, and washed withwater. The precipitate is purified by dissolving it in methyl Cellosolveand precipitating with water. After repeating the purification step twoadditional times, 1-[-v-methyl-/3,/3'-bis-(2',5'-dihydroxyphenyl)diethylamino] 5 nitro-anthraquinone, exhibitingan absorption maximum, in dimethylformamide, at 500 mu, e=13,500, isobtained, possibly mixed with unreacted 1,5-dinitro-anthraquinone.

The following nonlimiting example illustrates the use of a dye developerin the processes of this invention.

Example 2 Percent Sodium carboxymethyl cellulose 4.5 Potassium bromide0.2 l-phenyl-3-pyrazolidone 0.2 Sodium hydroxide 2.0

between said photosensitive element and an image-receiving element assaid elements are brought into superposed relationship. Theimage-receiving element comprises a cellulose acetate-coated barytapaper which has been coated with a 4% solution of Nylon Type F 8 (tradename of E. I. du Pont de Nemours & Co., Wilmington, Delaware, forN-methoxymethyl polyhexamethylene adipamide) in isopropanol. After animbibition period of approximately one minute, the image-receivingelement is separated and contains a salmon pink positive image of thephotographed subject.

It should be noted that certain dye developers are sensitive to pHchanges. Since the dye developer is rendered effective by solution in anaqueous alkaline processing composition, it accordingly is necessary toassure that the environment in which the transferred and unreacted dyedeveloper is deposited has or is capable of attaining the requisite pHaffording the desired color to the diffused dye developer. This may beaccomplished by use of a volatile basic compound such as diethylamine inthe liquid processing composition. If sodium hydroxide is utilized inthe processing liquid, it becomes carbonated after processing and bycontact with the air and this is effective to provide the desired pHchange. Further control of the pH of the transferred and unreacted dyedeveloper may be had by utilizing an image-receiving element which isdiificultly penetrable by alkali, for example an appropriate nylon suchas N-methoxymethyl polyhexamethylene adipamide, or by the use of areceiving element in which an acid or an acid-forming compound, e.g.,oleic acid, has been incorporated.

It will be noted that the liquid processing composition may, and in theabove example does, contain a small amount of an auxiliary oraccelerating developer, such as Metol, amidol, benzylaminophenol, or a3-pyrazolidone, such as 1-phenyl-3-pyrazolidone (Phenidone). Thepreferred auxiliary developer is l-phenyl-3-pyrazolidone. This auxiliarydeveloper serves to accelerate and possibly initiate the action of thedye developer. A portion of the dye developer may be oxidized by anenergy transfer reaction with oxidized auxiliary developer.

The dye developers of this invention may be used also in conventionalphotographic processes, such as tray or tank development of conventionalphotosensitive films, plates or papers to obtain black-and-white,monochromatic or toned prints or negatives. By way of example, adeveloper composition suitable for such use may comprise an aqueoussolution of approximately 1 to 2% of the dye developer, 1% sodiumhydroxide, 2% sodium sulfite and 0.05% potassium bromide. Afterdevelopment is completed, any unreacted dye developer is washed out ofthe photosensitive element, preferably with an alkaline washing mediumor other medium in which the unreacted dye developer is soluble. Theexpression toned is used to designate photographic images wherein thesilver is retained with the precipitated dye, whereas monochromatic isintended to designate dye images free of silver.

It should be noted that the dye developers of this invention areself-sulficient to provide the desired color image and do not dependupon coupling reactions to produce the desired color. They thus providea complete departure from conventional photographic color processes inwhich the color is produced by a coupling reaction involving theoxidized developing agent.

It should be noted that it is within the scope of this invention to usemixtures of dye developers to obtain a desired color.

It will be apparent that, by appropriate selection of theimage-receiving element from among suitable known opaque and transparentmaterials, it is possible to obtain either a colored positive reflectionprint or a colored positive transparency. Likewise, the inventiveconcepts herein set forth are adaptable for multicolor work by the useof special photographic materials, for example, film materials of thetype containing two or more photosensitized elements associated with anappropriate number of imagereceiving elements and adapted to be treatedwith one or more liquid processing compositions, appropriate dyedevelopers suitable to impart the desired subtractive colors beingincorporated in the photosensitized elements or in the liquid processingcompositions. Examples of such photographic materials are disclosed inthe US. Patent No. 2,647,049 to Edwin H. Land.

The inventive concepts herein set forth are also adaptable for theformation of colored images in accordance with the photographic productsand processes described and claimed in the copending application ofEdwin H. Land, Serial No. 448,441, filed August 9, 1954, now US. Patent2,968,554 issued January 17, 1961, and also the copending application ofEdwin H. Land and Howard G. Rogers, Serial No. 565,135, filed February13, 1956.

In the preceding portions of the specification, the expression color hasbeen frequently used. This expression is intended to include the use ofa plurality of colors to obtain black, as well as the use of a singleblack dye developer.

Since certain changes may be made in the above prod ucts, compositionsand processes without departing from the scope of the invention hereininvolved, it is intended that all matter contained in the abovedescription shall be interpreted as illustrative and not in a limitingsense.

What is claimed is:

1. A photographic developer composition comprising an aqueous a kalinesolution containing at least one auxiliary silver halide developingagent and a dye developer having an anthraquinone nucleus, at least oneand not more than two of the nuclear carbon atoms in the one, four, fiveand eight positions of said anthraquinone nucleus having linked directlythereto a group of the formula:

wherein R is selected from the group consisting of methyl and ethylgroups, R is an alkylene group containing less than six carbon atoms andeach Y is selected from the group consisting of orthoandpara-dihydroxyphenyl radicals.

2. A photographic developer composition comprising an aqueous alkalinesolution containing at least one auxiliary silver halide developer agentand a dye developer having an anthraquinone nucleus, the nuclear carbonin the one position of said anthraquinone nucleus having directly linkedthereto a group of the formula:

wherein R is selected from the group consisting of methyl and ethylgroups, R is an alkylene group containing less than six carbon atoms andeach Y is selected from the group consisting of orthoandpara-dihydroxyphenyl radicals.

3. A photographic developer composition as defined in claim 2 whereineach Y is a para-dihydroxyphenol group.

4. A photographic developer composition as defined in claim 3 wherein Ris a methyl group.

5. A photographic developer composition comprising an aqueous alkalinesolution containing at least one auxiliary silver halide developingagent and 1-[amethyl-/3,/3'- bis- 2,5'-dihydroxyphenyl) -diethylamino]-5-nitro-anthraquinone.

6. A photographic product comprising a plurality of layers including asilver halide emulsion layer and a layer, contiguous with said silverhalide emulsion layer, containing a dye developer having ananthraquinnone nucleus, at least one and not more than two of thenuclear carbon atoms in the one, four, five and eight positions of saidanthraquinone nucleus having linked directly thereto a group of theformula:

wherein R is selected from the group consisting of methyl and ethylgroups, R is an alkylene group containing less than six carbon atoms andeach Y is selected from the group consisting of orthoandpara-dihydroxyphenyl radicals.

7. A photographic product comprising a plurality of layers including asilver halide emulsion layer and a layer, contiguous with said silverhalide emulsion, containing a dye developer having an anthraquinonenucleus, the nuclear carbon in the one position of said anthraquinonenucleus having directly linked thereto a group of the formula:

wherein R is selected from the group consisting of methyl and ethylgroups, R is an alkylene group containing less than six carbon atoms andeach Y is selected from the group consisting of orthoandpara-dihydroxyphenyl radicals.

8. A photographic product as defined in claim 7 wherein each Y is apara-dihydroxyphenyl group.

9. A photographic product as defined in claim 7 wherein R is a methylgroup.

10. A photographic product comprising a plurality of layers including asilver halide emulsion layer and a layer, contiguous with said silverhalide emulsion layer, containing1-[ot-methyl-iifl-bis-(2,5-dihydroxphenyl) diethylamino]-5-nitro-anthraquinone.

11. In a process of forming a photographic image in color, the stepswhich comprise developing an exposed silver halide emulsion with anaqueous alkaline solution containing a dye developer having ananthraquinone nucleus, at least one and not more than two of the nuclearcarbon atoms in the one, four, five and eight positions of saidanthraquinone nucleus having linked directly thereto a group of theformula:

wherein R is selected from the group consisting of methyl and ethylgroups, R is an alkylene group containing less than six carbon atoms andeach Y is selected from the group consisting of orthoandpara-dihydroxyphenyl radicals, providing as a function of thedevelopment an imagewise distribution of unoxidized dye developer inundeveloped areas of said emulsion, and transferring at least part ofsaid distribution of said unoxidized dye developer, by imbibition, fromsaid emulsion to an image-receiving layer in superposed relationshipwith said emulsion to impart to said image-receiving layer a positivedye image.

12. In a process of forming a photographic image in color, the stepswhich comprise developing an exposed silver halide emulsion with anaqueous alkaline solution containing a dye developer having ananthraquinone nucleus, the nuclear carbon in the one position of saidanthraquinone nucleus having directly linked thereto a group of theformula:

wherein R is selected from the group consisting of methyl and ethylgroups, R is an alkylene group containing less than six carbon atoms andeach Y is selected from the group consisting of orthoandpara-dihydroxyphenyl radicals, providing as a function of thedevelopment an imagewise distribution of unoxidized dye developer inundeveloped areas of said emulsion, and transferring at least part ofsaid distribution of said unoxidized dye developer, by im'bibition, fromsaid emulsion to an image-receiving layer in superposed relationshipwith said emulsion to impart to said image-receiving layer a positivedye image.

13. A process as defined in claim 12 wherein each Y is apara-dihydroxy-phenyl group.

14. A process as defined in claim 12 wherein R is a methyl group.

15. A process as defined in claim 12 wherein said dye developer isla-methyl-B,fl'-bis( 2,5 '-dihydroxyphenyldiethylamino]-5-nitro-anthraquinone.

16. A process as defined in claim 12 wherein said aqueous alkalinesolution contains a small amount of an auxiliary silver halidedeveloping agent.

17. A process of developing an exposed photosensitive silver halideemulsion which comprises developing an exposed silver halide emulsionwith an aqueous alkaline processing solution containing a dye developerhaving an anthraquinone nucleus, at least one and not more than two ofthe nuclear carbon atoms in the one, four, five and eight positions ofsaid anthraquinone nucleus having linked directly thereto a group of theformula:

GHQ-E Y wherein R is selected from the group consisting of methyl andethyl groups, R is an alkylene group containing less than six carbonatoms and each Y is selected from the group consisting of orthoandpara-dihydroxyphwyl radicals.

18. A process of developing an exposed photosensitive silver halideemulsion which comprises developing said exposed silver halide emulsionwith an aqueous alkaline processing solution containing a dye developerhaving an anthraquinone nucleus, the nuclear carbon atom in the oneposition of said anthraquinone nucleus having directly linked thereto agroup of the formula:

om-R Y 10 processing solution containing 1-[a-methy1-B,;8'-bis-(2,5-dihydroxyphenyl)-diethylarnino]-5-nitro anthraquinone. 22. A process asdefined in claim 18 wherein said aqueous alkaline solution contains asmall amount of an auxiliary silver halide developing agent.

References Cited in the file of this patent UNITED STATES PATENTS 102,132,169 Kurnetat Oct. 4, 1938 2,206,126 Schinzel July 2, 19402,292,306 Vi-tturn et a1. Aug. 4, 1942 2,353,010 BuXbaurn July 4, 19442,434,765 Grossmann Jan. 20, 1948 15 2,698,244 Land Dec. 28, 19542,710,804 Schenk June 14, 1955 2,774,668 Rogers Dec. 18, 1956 2,892,710Cohler et -al June 30, 1959 2,983,605 Corley May 9, 1961 20 2,983,606Rogers May 9, 1961 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONPatent No. 3,047,386 July 31, 1962 Elkan R. Blout et a1.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 3, lines 18 to 23, the formula should appear as shown belowinstead of as in the patent:

line 25, for "nitro group or" read nitro group or a llnes 26 to 32, theformula should appear as shown below lnstead of as in the patent:

H-R -Y CHCH2Y 1 same column 3, lines 61 to 75, the formula should appearas shown below instead of as in the patent:

column 6, line 74, for "developer", first occurrence, read developingcolumn 7, line 15, for "para-dihydroxyphenol" read para-dihydroxyphenylSigned and sealed this 17th day of September 1963.

(SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD Attesting Officer Commissioner of Patents

1. A PHOTOGRAPHIC DEVELOPER COMPOSITION COMPRISING AN AQUEOUS ALKALINESOLUTION CONTAINING AT LEAST ONE AUXILIARY SILVER HALIDE DEVELOPINGAGENT AND A DYE DEVELOPER HAVING AN ANTHRAQUINONE NUCLEUS, AT LEAST ONEAND NOT MORE THAN TWO OF THE NUCLEAR CARBON ATOMS IN THE ONE FOUR, FIVEAND EIGHT POSITIONS OF SAID ANTHRAQUINONE NUCLEUS HAVING LINKED DIRECTLYTHERETO A GROUP OF THE FORMULA: